To confront this " colleague?"

[malificent7]

On placement.All students. Failed a test . I can retake it. One colleague mocked it by saying " i heard you have to get 35 marks wrong to get a fail."
So she had worked out out then told me when she knew i was feeling shit sbout it. And also goes on about how amazing she is and makes negative comments about other people's performance....even qualified staff way above us. She told me that the staff thought another colleague " wasn't that good."
She never says any of this to their face btw ....always behind peoples back.
We are all students btw so learning and none of us are 100% amazing.

@TillyTopper

Just ignore her, concentrate on your course, and get on with life. Don't let her suck your energy.

This. Don’t engage at all.

The fact that you had to mention her looks, to complain about her behaviour, tells me a lot about you.

Ignore her and minimise contact with her. Also don't disclose any test results you get, there are always types who wan crow about there results. Just reply with something like "I did better than I was expecting" or " I am a little bit diappointed" with my result but hey ho" sort of thing.
If you are feeling brave you could always ask her very loudly "Are you always such a horrible bitch", make sure you have an audience for that one.

Bloody hell, their, not there.

@Seafog

The fact that you had to mention her looks, to complain about her behaviour, tells me a lot about you.

Do you think some women don’t use their looks to get what they want? Mainly from men? If this woman was a plain Jane or even ugly the men wouldn’t be paying her nonsense nowhere near as much attention. So stop trying to put the OP down because most of us here knew why she commented on the girls looks. She also commented on her age, which I notice you failed to pick her up on.

Just ignore her and let her dig her own hole.

If you're only there two more days I'd probably leave it. You could try, "I'm not comfortable talking about this." Or no response at all when she looks to you for affirmation.